Mount Fuji

An equilateral triangle inscribed in a circle is divided by a diameter parallel to one of it’s sides. What is the proportion light : dark blue?

Scroll down for a solution to this problem.


The proportion light to dark blue is 4 : 5.

Solution by Nèstor Abad.

This solution uses the fact that the diameter passes through the incenter of the triangle, at two-third height from the triangle base.


Mount Fuji
Covered with snow
A sacred place to go
One can climb on Mount Fuji
Not in a hurry but slowly
He is so well known
With it’s white and beautiful cone
Sightseers and climbers
All together
Love you better and better
They have a lot of fun
In the land of the rising sun


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